This invention relates generally to irrigation sprinkler systems of the type having one or more irrigation sprinklers coupled to a water supply line which is typically buried underground. More particularly, this invention relates to an improved and adjustable riser for coupling an irrigation sprinkler to a water supply line, wherein the riser permits the elevational position of the associated sprinkler to be adjusted quickly and easily to a selected height relative to the surrounding ground level.
Irrigation sprinkler systems are generally well known in the art, wherein a plurality of individual irrigation sprinkler heads or units are coupled with a water supply line to provide irrigation water to a selected terrain area, such as in a turf, golf, or agricultural irrigation environment. The water supply line is often buried underground, and is coupled by angled joints and vertically extending risers to the individual sprinkler units. The lengths of these risers are individually chosen to achieve partial or full exposure of the individual sprinkler units at a selected height relative to the ground level in accordance with the buried depth of the supply line as well as the type and height of the specific surrounding vegetation. Accordingly, when the irrigation system is initially installed, it is normally necessary to provide risers of several different lengths, or alternately to cut individual risers of custom lengths.
Over time, the ground level and the height of vegetation associated with an irrigation sprinkler system can change. That is, soil and organic matter can build up or erode from the vicinity of individual sprinkler units, to result in a need to adjust the elevational position of one or more sprinkler units. Moreover, vegetation such as shrubs and the like can grow significantly, or taller vegetation can be trimmed to a shorter height or otherwise replaced with shorter plants to result in a need to adjust the elevational position of one or more sprinkler units. In a typical irrigation system, such positional adjustment has required removal and replacement of risers, with at least some attendant digging to expose the buried water supply line in order to access and replace risers.
Adjustable riser arrangements have been proposed in an effort to permit vertical positional adjustment of sprinkler units without requiring riser removal or replacement. Such adjustable riser arrangements have included articulated riser assemblies having several swingably interconnected segments to accommodate vertical adjustment of a sprinkler unit attached thereto. See, for example, U.S. Pat. Nos. 5,040,729 and 5,242,112. These articulated riser assemblies, however, inherently utilize several component parts which undesirably increase system cost and further provide multiple potential water leakage sites between the movably interconnected components. Moreover, at least some digging is often required to at least partially expose the interconnected joint and riser segments in order to accommodate the desired vertical adjustment. In an alternative concept, elevational adjustment structures have been provided in the sprinkler unit, to permit vertical adjustment of a spray nozzle relative to the surrounding terrain. See, for example, U.S. Pat. No. 3,317,144. However, this approach undesirably increases the cost and complexity of each sprinkler unit, and further has not permitted bidirectional vertical adjustment in the absence of full circle rotation of at least part of the sprinkler unit. The requirement for full circle rotation to achieve elevational adjustment is especially undesirable in solenoid and hydraulically actuated sprinklers since it results respectively, in tangling of electrical wires connected to a solenoid actuator and may require disconnection of conduits connected to the hydraulic valve actuator.
The present invention is directed to an improved adjustable riser for coupling an irrigation sprinkler to a water supply line, wherein the elevational position of the sprinkler can be vertically raised or lowered quickly and easily without requiring full circle rotation of any component, and further without requiring any significant movement of soil in the vicinity of the sprinkler.